The present invention, in some embodiments thereof, relates to nanotechnology and, more particularly, but not exclusively, to a nanowire structure, a method of fabricating a nanowire and systems incorporating the nanowire.
Nanoscience is the science of small objects and is one of the most important research frontiers in modern science. These small objects are of interest from a fundamental view point since all properties of a material, such as its melting point and its electronic and optical properties, change when the particles that make up the material become nanoscopic. With new properties come new opportunities for technological and commercial development, and applications of nanometric objects have been shown or proposed in areas as diverse as micro- and nanoelectronics, nanofluidics, coatings, paints and biotechnology.
It is well established that future development of microelectronics, magnetic recording devices and chemical sensors will be achieved by increasing the packing density of device components. Traditionally, microscopic devices have been formed from larger objects, but as these products get smaller, below the micron level, this process becomes increasingly difficult. It is therefore appreciated that the opposite approach is to be employed, essentially, the building of microscopic devices from using a bottom up approach, primarily via objects of nanometric dimensions. Self-assembled nanostructures, allow controlled fabrication of novel nanoscopic materials and devices.
In particular, wire-like nanostructures have attracted extensive interest over the past decades due to their great potential for addressing some basic issues about dimensionality and space confined transport phenomena as well as related applications. Wire-like nanostructures often have distinctive properties and can be used as transparent conducting materials and gas sensors.
Widely used objects in nanotechnology are fullerene carbon nanotubes which are elongated objects having carbon hexagonal mesh sheet of carbon substantially in parallel with their axis. Also known are other types of nanostructures, such as peptide nanotubes assembled through hydrogen-bonding interactions of peptide building blocks, and lipid nanotubes self-assembled from lipid surfactants.
Heretofore, several approaches have utilized to assemble gold nanostructures by conjugating them with biomolecules. For example, gold nanowires were fabricated by the intercalation of gold nanoparticles into a double-stranded DNA, followed by photochemical covalent attachment of the intercalator with a DNA template [Patolsky et al., Angew. Chem. Int. Ed. 2002, 41, 2323]. More recently, linear arrays of gold nanoparticle were fabricated using specially designed peptides that self-assemble into β-sheet fibrils exhibiting a laminated morphology [M. S. Lamm, N. Sharma, K. Rajagopal, F. L. Beyer, J. P. Schneider, Adv. Mater. 2008, 20, 447], and micrometric-size crystal structures of gold nanoparticles were assembled via various DNA linkers [Park et al., Nature 2008, 451, 553].
Formation of films of gold nanoparticles has been disclosed, e.g., by Brust et al. in Nano Lett. 2001, 1, 189. Gold nanoparticles stabilized by the adsorption of a monolayer of alkanethiolates and chloroform solutions of the stabilized nanoparticles were spread and evaporated at a water-air interface to form Langmuir films. Another technique is disclosed in Kim et al., J Am Chem Soc 2001, 123, 4360. In this technique, colloidal suspension of BaCrO4 nanorods was spread on a water surface of a Langmuir-Blodgett trough, and subsequently compressed, starting with a nonzero surface pressure, to form two-dimensional nanorod mono- and multilayers.